Pinpoint Test E: B105A:12, B105A:14, B1A61:11, B1A61;15, B1A69:12, B1A69:14
WARNING: This page is about a different car, the 2023 Ford Bronco. However, it is still accessible from the selected car via links, so may be relevant.
- Refer to
MANUAL CLIMATE CONTROL SYSTEM
for schematic and connector information.
Normal Operation and Fault Conditions
In-Vehicle Temperature and Humidity Sensor, REFER to: Climate Control System - Vehicles With: Electronic Manual Temperature Control (EMTC) - System Operation and Component Description .
DTC Fault Trigger Conditions
DTC Description Fault Trigger Condition HVAC B105A:12 Cabin Temperature Sensor Fan: Circuit Short To Battery Module senses a short to battery for the fan motor circuit. HVAC B105A:14 Cabin Temperature Sensor Fan: Circuit Short To Ground Or Open Module senses a short to ground or open for the fan motor circuit. HVAC B1A61:11 Cabin Temperature Sensor: Circuit Short To Ground Module senses lower than expected voltage on the temperature sensor feedback circuit, indicating a short to ground. HVAC B1A61:15 Cabin Temperature Sensor: Circuit Short To Battery Or Open Module senses unexpected voltage on the circuit for the cabin temperature sensor. HVAC B1A69:12 Humidity Sensor: Circuit Short To Battery Module senses a short to battery for the humidity sensor. HVAC B1A69:14 Humidity Sensor: Circuit Short To Ground Or Open Module senses no voltage on the circuit for the humidity sensor, indicating a short to ground or open. Possible Sources
- Wiring, terminals or connectors
- In-vehicle temperature and humidity sensor
- HVAC control module
NOTE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may cause damage to the connector. - E1 CHECK THE IN-VEHICLE TEMPERATURE AND HUMIDITY SENSOR CIRCUITS FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect In-vehicle temperature and humidity sensor C233.
- Disconnect BCM fuse 21 (5A).
- Ignition ON.
- Measure:
Positive Lead Measurement / Action Negative Lead C233 Pin 1 Ground Pin - C233 Pin 2 Ground Pin - C233 Pin 3 Ground Pin - C233 Pin 4 Ground Pin - C233 Pin 5 Ground Pin - C233 Pin 6 Ground Pin -
Is any voltage present?
Yes REPAIR the circuit in question. No GO to E2 - E2 CHECK THE IN-VEHICLE TEMPERATURE AND HUMIDITY SENSOR CIRCUITS FOR A SHORT TO GROUND
- Ignition OFF.
- Measure:
Positive Lead Measurement / Action Negative Lead C233 Pin 1 Ground Pin - C233 Pin 2 Ground Pin - C233 Pin 3 Ground Pin - C233 Pin 4 Ground Pin - C233 Pin 5 Ground Pin - C233 Pin 6 Ground Pin -
Are the resistances greater than 10, 000 ohms?
Yes GO to E3 No REPAIR the circuit in question. - E3 CHECK THE IN-VEHICLE TEMPERATURE AND HUMIDITY SENSOR CIRCUITS FOR AN OPEN CIRCUIT
- Measure:
Positive Lead Measurement / Action Negative Lead C233 Pin 1 C228B Pin 27 C233 Pin 2 C228B Pin 29 C233 Pin 4 C228B Pin 19 Positive Lead Measurement / Action Negative Lead C233 Pin 3 C228A Pin 3 C233 Pin 5 C228A Pin 2 Positive Lead Measurement / Action Negative Lead C233 Pin 6 BCM fuse 21 (5A) socket (component side)
Are the resistances less than 3 ohms?
Yes INSTALL a new in-vehicle temperature and humidity sensor. REFER to: In-Vehicle Temperature and Humidity Sensor . CLEAR all Diagnostic Trouble Codes (DTCs). CARRY OUT the HVAC control module self-test. TEST the system for normal operation. If the concern is still present, GO to E4 No REPAIR the circuit in question. - Measure:
- E4 CHECK FOR CORRECT HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE OPERATION
- Ignition OFF.
- Disconnect and inspect all HVAC control module electrical connectors (if not previously disconnected).
- Repair:
- corrosion (install new connector or terminal - clean module pins)
- damaged or bent pins - install new terminals or pins
- pushed-out pins - install new pins as necessary
- Connect all HVAC control module electrical connectors. Make sure they seat and latch correctly.
- Operate the system and determine if the concern is still present.
Is the concern still present?
Yes CHECK OASIS for any applicable service articles: TSB, GSB, SSM or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new HVAC control module. REFER to: Heating, Ventilation and Air Conditioning (HVAC) Control Module . No The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.